Obama v Romney: US election poll tracker

The race to the White House is a close call with the two candidates neck-and-neck in the days before the election. Use our polltracker to follow the changing support for Democratic incumbent Barack Obama and his Republican rival Mitt Romney.

The BBC poll of polls uses the same methodology as the London School of Economics, known as the median smoothing method.

Looking at the five most recent polls it takes the middle value for each candidate, ie, the value which falls between two figures that are higher and two figures that are lower.